Dave Jamieson says he's noticed fewer birds and bird species at his Bright's Grove dairy farm in recent years, and wants to know why. “They're just not around at all... I can go out all day and I'm lucky to see one,” he said, pointing to the disappearance of barn swallows (Hirundo rustica), chimney swifts (Chaetura pelagica) and other birds. “How come nobody notices these birds aren't around?” Jamieson, who has lived on the property all his life, said he used to see more than a dozen barn swallow nests at one time. “In the last three years, there's only been about four; and this is the first year they've never had babies,” he said. “Even when you drive along the road, and look at the hydro lines – where birds used to sit all the time – they're not there anymore.” Jamieson said he's so concerned, he's contacted Sarnia City Hall and the Ministry of Natural Resources office in Chatham, but hasn't received a response. But a biologist with Bird Studies Canada said Jamieson's concerns reflect new and alarming trends among Canada's bird populations. “There's a real dramatic change in the bird landscape going on in Canada,” said Jody Allair, biologist and science educator, pointing to a ground-breaking report released last year called The State of Canada's Birds.
The document, spearheaded by Bird Studies Canada, Environment Canada, and a number of other groups, marked the first-ever major assessment of Canada's bird populations, drawing on 40 years of data.
It revealed that Canadian breeding bird populations have dropped 12% across the board, since 1970.
Two particular groupings of birds experiencing significant declines – particularly in the lower Great Lakes area – are the grassland and aerial insectivores, Allair said.
“Barn swallows are declining quite dramatically; they are now a designated threatened species in Canada,” he said.
The report notes that aerial insectivores – birds that catch insects in flight – primarily swallows, have declined here and across the country. In this region, the chimney swift, purple martin (Progne subis) and bank swallow (Riparia riparia) populations have all declined by approximately 95% since 1970.
Though the exact cause of the decline is unknown, the report points to a number of factors including reduced insect populations and loss of nesting habitat.
Meanwhile, Grassland birds like meadowlarks (Sturnella magna) and bobolinks (Dolichonyx oryzivorus) have declined by 70% with several species at risk of local extinction.
“The major theme here is that, some birds that we used to think were quite common, like barn swallows, are no longer that way,” said Allair. “People still see them, but they don't realize there are far fewer of them now than there were even 20 years ago.”
Allair said the next step is identifying the causal factors for decline; some theories include climate change, and changes in insect abundance.
“Whether you're a birder or not, it's really important... birds are an important indicator of change,” he said. “When we see changes in bird populations, we know there are other changes happening in the environment, and we need to pay attention.
Source: Chatham Daily News, 30 August 2013
http://www.chathamdailynews.ca/2013/08/30/report-reflects-dramatic-decl…
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